We were very happy with the Fisher Price booster seat. We used it daily for 18 months. It has a harness (not 5 point) and machine washable tray. We used to take it on holidays, to restaurants and when visiting people's houses as it's light and compact and straps securely to most dining chairs. It is also size adjustable. HTH.

The stokke Tripp trapp chairs are amazing, and can be used for years and years. I have 2, second hand off eBay and I love them. They are just fab for bringing your child up to the table. Both kids love them.

If they aren't an option I have seen the cheaper copies and will come back and post where to get them if I remember where I saw them

We didn't get the tray table (wasn't an option when we bought it but we wouldn't have used it anyway), but the chair as a whole is fantastic!

The straps held DS2 in securely from 6 months onwards, and we've only just removed the rail now (he's around 22 months old) as he has been climbing in and out by himself and it seemed far safer to have it off.

I think it is going to wear a lot better than the one we got DS1 from Mothercare. The foot plate is starting to wear on his so we may end up getting the same one as DS2 for longevity. If we could afford Stokke Tripp Trapps we'd have got them, but these seem to be the next best option.